Since the 1960's an overwhelming amount of in-house and custom engineering software has been written. In the effort to reduce the cost of maintaining existing codes and producing new applications, the recent introduction of the object-oriented design approach has proved successful. At the same time graphical user interfaces are gaining in popularity to improve the usability and versatility of an application. This thesis investigates the application of the object-oriented approach to the design of a graphical user interface for an engineering design application. The development of an object-oriented graphical user interface for the NASA Engine Performance Program, a turbine engine design code is presented. The design of the new object-oriented graphical user interface for extensibility and re-usability is discussed. Design considerations for integration of the interface with procedural and object-oriented versions of the conceptual aircraft design program, ACSYNT, are explained. An existing PHIGS-based object-oriented graphical user interfacing framework is extended and built upon to develop the class structure of the interface. The class organization is presented in commonly used notation and described in detail. / Master of Science

No / The results from previous experiments using structured musical stimuli to communicate coordinate locations within a graphical grid, navigation of an auditory cursor and simple shapes are used as a basis for further exploratory research to communicate diagrams. An experimental framework program (called AudioGraph) provided a platform for investigating musical information processing for blind users. Under this platform, simple arrangements of shapes (forming diagrams) were communicated to users using structured musical stimuli. Meaningfully arranged graphical shapes (at least for the visual sense) were communicated in the absence, and in the presence of a particular perceptual context or different perceptual contexts. The results indicated that perceptual context played an important role in the interpretation of the structured musical stimuli that communicated simple diagrams. The paper concludes with a discussion on the implications of the results, the role of context and the use of structured musical stimuli to communicate graphical information to visually impaired users.

<p>This thesis presents a set of concepts and a general design approach for designing Mixed Reality environments based on the idea that the physical (real) world and the virtual (digital) world are equally important and share many properties. Focus is on the design of a technology infrastructure intended to relieve people from some of the extra efforts currently needed when performing activities that make heavy use of both worlds. An important part of the proposed infrastructure is the idea of creating Physical-Virtual Artefacts, objects manifested in the physical and the virtual world at the same time.</p><p>The presented work challenges the common view of Human-Computer Interaction as a research discipline mainly dealing with the design of “user interfaces” by proposing an alternative or complementary view, a physical-virtual design perspective, abstracting away the user interface, leaving only physical and virtual objects. There are at least three motives for adopting such a design perspective: 1) people well acquainted with specific (physical and virtual) environments are typically more concerned with the manipulation of (physical and virtual) objects than the user interface through which they are accessed. 2) Such a design stance facilitates the conceptualisation of objects that bridge the gap between the physical and the virtual world. 3) Many physical and virtual objects are manifested in both worlds already today. The existing conceptual link between these physical and virtual objects has only to be complemented with causal relations in order to reduce the costs in crossing the border between the physical and the virtual world.</p><p>A range of concepts are defined and discussed at length in order to frame the design space, including<i> physical-virtual environment gap, physical-virtual activity, physical-virtual artefact, </i>and<i> physical-virtual environment</i>.</p><p>Two conceptual models of physical-virtual space are presented as a result of adopting the physical-virtual design perspective: for the analysis of object logistics in the context of physical-virtual activities, and for describing structural properties of physical-virtual space respectively. A prototype system offering some degree of physical-virtual infrastructure is also presented.</p>

There is a growing interest in bringing online and streaming content to the television. Gaming platforms such as the PS3, Xbox 360 and Wii are at the center of this digital convergence; platforms for accessing new media services. This presents a number of interface challenges, as controllers designed for gaming have to be adapted to accessing online content. We conducted a user study examining the limitations and affordances of novel game controllers in an interactive TV (iTV) context and compared them to "second display" approaches using tablets. We looked at task completion times, accuracy and user satisfaction across a number of tasks and found that the Wiimote is most liked and performed best in almost all tasks. Participants found the Kinect difficult to use, which led to slow performance and high error rates. We discuss challenges and opportunities for the future convergence of game consoles and iTV. We also analyzed the usability of the interfaces themselves with respect to each device. Accuracy ratings and context of task type were used to determine ideal component attributes such as button size and spacing. Additional strategies like snapping cursor to buttons in the case of small targets were also suggested. Paying attention to the strengths and weaknesses of each input method, we put forth a set of design recommendations for future iTV interfaces that leverage novel input devices. / Graduation date: 2012

This thesis presents a set of concepts and a general design approach for designing Mixed Reality environments based on the idea that the physical (real) world and the virtual (digital) world are equally important and share many properties. Focus is on the design of a technology infrastructure intended to relieve people from some of the extra efforts currently needed when performing activities that make heavy use of both worlds. An important part of the proposed infrastructure is the idea of creating Physical-Virtual Artefacts, objects manifested in the physical and the virtual world at the same time. The presented work challenges the common view of Human-Computer Interaction as a research discipline mainly dealing with the design of “user interfaces” by proposing an alternative or complementary view, a physical-virtual design perspective, abstracting away the user interface, leaving only physical and virtual objects. There are at least three motives for adopting such a design perspective: 1) people well acquainted with specific (physical and virtual) environments are typically more concerned with the manipulation of (physical and virtual) objects than the user interface through which they are accessed. 2) Such a design stance facilitates the conceptualisation of objects that bridge the gap between the physical and the virtual world. 3) Many physical and virtual objects are manifested in both worlds already today. The existing conceptual link between these physical and virtual objects has only to be complemented with causal relations in order to reduce the costs in crossing the border between the physical and the virtual world. A range of concepts are defined and discussed at length in order to frame the design space, including physical-virtual environment gap, physical-virtual activity, physical-virtual artefact, and physical-virtual environment. Two conceptual models of physical-virtual space are presented as a result of adopting the physical-virtual design perspective: for the analysis of object logistics in the context of physical-virtual activities, and for describing structural properties of physical-virtual space respectively. A prototype system offering some degree of physical-virtual infrastructure is also presented.

The Internet has shifted from the Web 1.0 era to the Web 2.0 era. In the contemporary era of web 2.0, the Internet is being used to build and reflect social relationships among people who share similar interests and activities. This is done through services such as Social Networking Sites (Facebook, Twitter etc.) and the web blogs. Currently, there is a very high usage of Social Networking Sites (SNSs) and blogs where people share their views, opinions, and thoughts. This leads to the production of a lot of data by people who post such content on SNSs. As a result, SNSs and blogs become the ideal platforms for opinion monitoring and the trend analysis. These SNSs and Blogs could be used by service providers for tracking what the public thinks or requires. The reason being, having such knowledge can help in decision making and future planning. If service providers can keep track of such views, opinions or thoughts with regard to the services they provide, they can better their understanding about the public or clients’ needs and improve the provision of relevant services. This research project presents a system prototype for performing opinion monitoring and trend analysis on Facebook. The proposed system crawl Facebook, indexes the data and provides user interface (UI) where end users can search and see the trending of a topics of their choice. The system prototype could also be used to check the trending topics without having to search. The main objective of this research project was to develop a framework that will contribute in improving the way government officials, companies or any service providers and normal citizens communicate regarding services they provide. This research project is premised on the conceptualization that if the government officials, companies or any service providers can keep track of the citizen’s opinions, views and thoughts with regards to services they provide it can help improve the delivery of such services. This research and the implementation of the trend analysis tool is undertaken in the context of the Siyakhula Living Lab (SLL), an Information and Communication Technologies for Development (ICTD) intervention for Dwesa marginalized community.

The Unified Modeling Language (UML) is the successor to the wave of object-oriented analysis and design (OOA&D) methods that appeared in the late '80s and early '90s. The class diagram is one of the most useful diagrams in UML. The class diagram technique has become truly central within object-oriented methods.

published_or_final_version / Computer Science / Doctoral / Doctor of Philosophy

<p>This thesis discusses the possibility of combining music and images through the use of metadata. Test subjects from different usability tests say they are interested in seeing images of the band or artist they are listening too. Lyrics matching the actual song are also something they would like to see. As a result an application for cellphones is created with Flash Lite which shows that it is possible to listen to music and automatically get images from Flickr and lyrics from Lyrictracker which match the music and show them on a cellphone.</p>

Recommender systems such as Amazon, offer uses recommendations, or suggestions of items to try or buy. We propose a novel classification of reasons for including explanations in recommender systems. Our focus is on the aim of effectiveness, or decision support, and we contrast it with other metrics such as satisfaction and persuasion. In user studies, we found that people varied in the features they found important, and composed a short list of features in two domains (movies and cameras). We then built a natural language explanation testbed system, considering these features as well as the limitations of using commercial data. This testbed was used in a series of experiments to test whether personalization of explanations affects effectiveness, persuasion and satisfaction. We chose a simple form of personalization which considers likely constraints of a recommender system (e.g. limited meta-data related to the user) as well as brevity. In these experiments we found that: 1. Explanations help participants to make decisions compared to recommendations without explanations, we saw as a significant decrease in opt-outs in item ratings – participants were more likely to be able to give an initial rating for an item if they were given an explanation, and the likelihood of receiving a rating increased for feature-based explanations compared to a baseline. 2. Contrary to our initial hypothesis, our method of personalization could damage effectiveness for both movies and cameras which are domains that differ with regard to two dimensions which we found affected perceived effectiveness: cost (low vs. high), and valuation type (subjective vs. objective). 3. Participants were more satisfied with feature-based than baseline explanations. If the personalization is perceived as relevant to them, then personalized feature-based explanations were preferred over non-personalized. 4. Satisfaction with explanation was also reflected in the proportion of opt-outs. The opt-out rate for the explanations was highest in the baseline for all experiments. This was the case despite the different types of explanation baselines used in the two domains.